Process for concentrating carnotite ores



Patented Dec. 25, 1923.

UNITED STATES- PATENT OFFICE WARREN F. BLEEQKER, OF BOULDER, COLORADO.

PROCESS FOR CONCENTRATING CARNOTITE ORES.

1T0 Drawing.

vented certain new and useful Improvements in Processes for Concentrating Carnotite Ores, of which the following is a specification.

the concentration of carnotite ores and its principal object is to effect by a simple chemical treatment of theores, a cleanand complete separation of its valuable con- 16 stituents from the silica and. other extraneous matter with which they are associated in the natural formation. Another object of the invention is to expediteand increase the efficiency of the reactions of 20 sulphuric acid in a process of concentrating carnotite ores, by the addition of hydrofluoric acid.

It is well known to those versed in the art that the action of sulphuric acid upon carnotite ore results in the partial solution and decomposition of the radium bearing minerals, and a partial freeing of these nunerals from the grains of sand to which the adhere, and it is for the purpose of ma in this decomposition more complete and o expediting the reaction of the acid b disintegration of the minerals that in tile present process hydrofluoric acid is employed in intermixture with the other acid.

The hydrofluoric acid required in the process of concentration may be produced by using in intermixture with the ore and sulphuric acid, a fluoride such as sodium fluoride or calcium fluoride, the latter being preferred. The sulphuric acid acting upon the fluoride, liberates hydrofluoric acid which in turn assists the sulphuric acid in decomposing and disintegrating the mineral content of the ore.

While the proportionate quantities of sulphuric acid and fluoride used in intermixture with the ore, must necessarily differ according to natural variations in the mineral content of the latter, the following proportions have been found to produce This invention relates to a process fori g so that a Perfect mixture y be Application filed February 1, 1922. Serial No. 588,487.

satisfactory results in carnotite ores-combined with an economical use of chemicals:

. Pounds. Carnotite ore 2000 Sulphuricacid (60 Baum) 500 Calcium fluoride (CaF The ore, in a finely, divided condition, is intermixed wlth the chemicals by rapid obtained before hardening sets in, and this mixture is diluted with about five hundred (500) pounds of water and subjected to attrition by standard methods. The attrition step of the process is followed by fur-- ther dilution of the material with several times its weight of water, after which the radium bearing mineral in the mixture is decanted from the free sands by any convenient method. It is advantageous to heat the mixture before decantation, to about the boiling point during a period of approximately one hour. The solids in the muddy solution carrying the radium values of the ore, are subsequently settled out of the liquid-and the sands may either go to waste, or be further subjected to attrition in order to increase the percentage of the 'radium recovered from the ore.

While the hydrofluoric acid is used mainly for its specific separative and disintegrating action upon the highly silicious radium bearing minerals of the carnotites whereby said minerals are freed from the sands with which they are associated, in a condition for ready decantation, its use alone would not have the desired effect, since its disintegrating action upon the particular ores to which the present process is especially adapted, is greatly increased in the presence of another mineral acid such as sulphuric acid.

What I claim and desire to secure by Letters Patent is:

1. The process of concentrating carnotite ores consisting in subjecting the ore to the combined disintegrating actions of sulfuric acid and hydrofluoric acid to a point at which the radium bearing mineral in a substantially 'solid condition is loosened stantiall from the sands, and then mechanically separatin the loosened mineral from the sand.

2. %he process of concentrating carnotite ores consisting in subjecting the ore to the combined disintegrating actions ofsulfuric acid and hydrofluoric acid to a point at which the radium bearing mineral in a sub solid condition is loosened from the san s, and then mechanically separating the loosened mineral from the sand, the hydrofluoric acid being produced in the ore b intermixing therewith in water, a fluorid e together with the sulfuric acid.

3. The process of concentrating carnotite ores consisting in subjecting the ore to the combined disintegrating actions of sulfuric acid and hydrofluoric acid to a point at which the radium bearing mineral in a substantiall solid condition is loosened from 20 the san s, and then mechanically separat- 1,47e,es1

ing the loosened mineral from the sand, the hydrofluoric acid being produced in the ore by intermixing therewith iniwater, calcium fluoride together with the sulfuric acid.

4. The process of concentrating carnotite ores consisting in subjecting the ore to the combined disintegrating actions of sulfur1c acid and hydrofluoric acid to a point at which the radium bearing mineral in a substantially solid condition is loosened from the sands, and then mechanically separating the loosened mineral from the sand, the hydrofluoric acid being produced in the ore by intermixing therewith in water twentyflve per cent of sulfuric acid and two and one half per cent of calcium fluoride.

In testimony whereof I have afiixed my signature.

WARREN F. BLEECKER. 

